Tapered core chuck with floating key



Feb. 12., 1968 D. N. OBENSHAIN TAPERED CORE CHUCK WITH FLOATING KEY Filed Aug. 23, 1966 2 Sheets-Sheet 1 l llllll III .lllI-IIIJ FIIIIIIL 3 OLD ART- YIINVENTOR Dav/'0 /V0e/ Obensha/n ATTORNEY Filed Aug. 25, 1966 Feb. 13, 1968 b. N. OBENSHAIN 3,368,769

TAPERED CORE CHUCK WITH FLOATING KEY 2 Sheets-Sheet 2 INVENTOR ATTORNEY United States Patent 3,368,769 TAPERED CORE CHUCK WITH V FLOATING KEY v David Noel Obenshain, Luke, Md., assignor to West Virginia Pulp and Paper Company, New York, N.Y., a corporation of Delaware Filed Aug. 23, 1966, Ser. No. 574,338 7 Claims. (Cl. 24268.4)

ABSTRACT OF THE DISCLOSURE A core chuck is presented for securing hollow cores thereon which includes a floating key mounted in a tapered chuck plug for receiving and positively engaging a plurality of different sized cores.

This invention deals with an improved tapered core chuck, particularly for use with rolls of paper, but not limited thereto.

In the paper, printing and allied industries, paper or other material in web form is usually handled in the form of rolls of the material wound on hollow metal, fiber or plastic cores.

These cores usually have a notch or opening in each end for engagement with keys which are mounted in chucks or plugs which fit into the ends of the core. These may be used for winding or unwinding the material.

FIGURE 1 shows a typical unwind stand equipped with my improved chuck;

FIGURE 2 shows a typical core used in the paper industry;

FIGURE 3 shows a common type of core chuck now in use;

FIGURE 4 shows in cross-section one form of my floating key design;

FIGURE 5 shows details of the floating key used in FIGURE 4;

FIGURES 6 and 7 show the floating key engaging two different sized cores; and

FIGURE 8 shows in cross-section a modification of my floating key design.

At the left side of FIGURE 1, the chuck 9 with floating key is mounted on a spindle 10, rotating in bearings 11, 12 carried by a floor mounted pedestal 13. The outboard end of the spindle is coupled to a brake mechanism 14 for applying tension to the web as it is being unwound. Core element 7 carries a roll of paper 8 which is to be unwound.

At the right side of FIGURE 1, the chuck 9, a plain chuck in this case, is mounted on a spindle 15 contained within the stem of an air operated piston 16 in a cylinder which is part of the pedestal 6. The air operated piston is used to position the chuck into the core or to withdraw the chuck therefrom.

The core element 7 shown in FIGURE 2 is typical of those used in the paper industry. The most common core material is steel pipe, and it generally ranges in size from three inches to eight inches in diameter in nominal pipe sizes. Fiber and plastic cores of various compositions are also used. Usually a notch or opening 17 about inch square is provided at each end of the core. The steel pipe cores are often made from seconds or culls, that is, pipe that for one reason or another does not meet the specifications for normal pressure piping service. For a given nominal size, the inside and outside diameters may vary considerably. For example, three inch steel pipe may range from 2 inches to 3%; inches inside di.

ameter.

'The core chuck, 18 shown in FIGURE 3 is one of the most common types now in use. It has a straight plug end 3,368,769 Patented Feb. 13, 1968 19 that fits inside the core 20. A shoulder or flange is provided for the core to butt against. The hardened steel key 2.1 is shown located in a bore in the chuck and held by a set screw 22. The key 21 engages a cooperating notch or opening in the core to prevent turning of the core on the chuck. If a brake or drive is used only at one end, the core chuck at the other end ofthe core is not usually equipped with a key.

Obviously, the plug of the chuck must be small enough in diameter to accept the smallest core that will be encountered. In case nominally sized three inch pipe cores are available, this diameter could not exceed 2 inches. FIGURE 3 illustrates what happens when a larger three inch core 20 is used. The core then has considerable clearance or play on the chuck 18. As the core turns, it continually rides up on the chuck and drops back, causing the roll mounted on the core to wobble and jump, creating an uneven draw of the web from the roll and wearing the chuck, its key and the end of the core.

To overcome these problems, a number of expanding types of chucks have been developed. In addition to being quite expensive, these chucks require considerable and continuing maintenance. Some are quite bulky and cannot be obtained in the smaller sizes.

Tapered chucks would be a very simple way to accommodate the core size variation, and, some fluted surface tapered chucks have been tried but, with little success. A fixed position for a key in a tapered chuck would be intolerable since it would not engage the notch in a small core, or else, it would not allow the larger core to move onto the taper far enough to prevent wobble.

My solution to this problem is to provide a floating key in the chuck plug that can fully engage the notch or opening in the core regardless of how far it rides onto the tapered chuck.

FIGURE 4 illustrates one form of my novel floating key design. The flat key 23 is mounted in a slot 24 formed in the tapered plug of the chuck 25. It pivots back and forth on a pin 26 located near the center of the chuck 25 and is forced to its extreme forward position by a spring 27 as shown. The spring 27 thus biases the key toward the cooperating core element or toward the small end of the taper. FIGURE 5 shows a detailed construction of the pivotal floating key 23 used in FIGURE 4. Chucks for any size cores may be readily interchanged by simply removing the mounting screws and switching chucks.

FIGURE 6 shows how the floating key 23 engages the opening in a small sized core 7, while FIGURE 7 shows how the floating key 23 engages a larger sized core 7.

FIGURE 8 illustrates another form which the floating key mechanism may have. In this instance the tapered chuck 28-is bored to receive a piston 29 in which the hardened steel key 30 is held by means of a set screw 31. The floating key 30 extends beyond the tapered surface of the chuck through a suitable slot 32 milled therein. Spring 33 is used to resiliently bias the piston and floating key 29 toward the small end of the chuck to engage a cooperating core element. The piston reciprocates or slides in the hereinbetore mentioned bore.

Obviously many other modifications could be made by those skilled in the, art, the invention only to be limited within the scope of the appended claims.

I claim:

1. A chuck for securing the hollow core of a web of material onto a rotatable supporting shaft comprising, a tapered chuck plug, mounted on a spindle for receiving a plurality of different sized core elements, an elongated slot formed in said chuck plug, and a floating key element mounted in said elongated slot to positively engage a notch in the end of any one of said core elements re- 3 gardless of the distance each core element rides onto said chuck plug.

2. The device as recited in claim 1, wherein said floating key is pivoted at one end thereof in said elongated slot, and, resilient means is provided to urge the key toward the core element.

3. The device as recited in claim 2, wherein said resilient means comprises a spring disposed in said elongated slot which fits into grooves formed in said floating key.

4. The device as recited in claim 1, wherein said floating key is attached to an element which is slidably received in the elongated slot formed in said chuck plug.

5. The device as recited in claim 4, wherein said slidably received element is a piston and said elongated slot is a bore.

6. The device as recited in claim 5, further comprising resilient means urging the piston and key toward the core element.

7. A conical chuck for securing the hollow core of a web of material onto a rotatable supporting shaft comprising, 'a tapered chuck plug mounted on a spindle for receiving a plurality of different sized core elements, an elongated slot formed in the plug of the chuck, a floating key element reciprocally mounted in said elongated slot and, a resilient means biasing the floating key element toward the smaller end of the chuck whereby the said floating key will positively engage a notch in the end of any one of said core elements regardless of the distance each core element rides onto said chuck plug.

References Cited UNITED STATES PATENTS 274,483 3/1883 Garceau 242-684 FOREIGN PATENTS 234,484 5/ 1911 Germany.

488,449 12/1929 Germany.

FRANK J. COHEN, Primary Examiner.

N. L. MINTZ, Assistant Examiner. 

